Amalgamator



Oct. 25, 1938. w. A.. GRANT ET AL 2,134,120

AMALGAMATOR Filed Sept. 14, 1957 Patented Oct. 25, 1938 PATENT} OFFICEAMALGAMATOR William Arthur Grant and Edward Freeman Roach, Vancouver,British Columbia, Canada Application September 14, 1937, Serial No.163,791

I 4 Claims.

Our invention relates to improvements in amalgamators. The objects ofthe invention are to provide means whereby the gold, platinum and othermetallic minerals of suitable specific gravity 5' are brought intointimate contact on all sides with the mercury and are immersed thereinto the extent that a static pressure equal tothe depth of immersion isapplied between the wanted particles and the mercury. Further objectsare to provide an amalgamator where the mercury is keptentirely cleanand oxidation of the mercury is prevented.

The invention consists of a device for forcing metallic mineral bearingliquid pulp downwardly into a body of mercury and effecting a turbulenceof the pulp and mercury below the normal mercury level, as will be morefully described in the following specification and shown in theaccompanying drawing, in which Fig lis a sectional view of theamalgamator.

Fig. 2 is a fractional plan View, taken on the line '2-2 of Figure 1.

'Fig. 3 is a diagrammatic view showing approximately the flow of pulpand mercury below the liquid level.

In the drawing like characters of reference indicate corresponding partsin each figure. v

The numeral I indicates a bowl having a pe= ripheral rim 2 over whichthetailing s flow to a suitable launder 3. The bowl'is provided with abottom outlet 4 through which. the mercury is discharged when cleaningout the amalgamator. Standing within the' bowl and separated therefromby legs 5, is an annular block 6 which is preferably of iron for thepurpose of weighting the amalgamating plate structure to be hereinafterdescribed.

Formed within the annular block 6 is a chamber generally indicated bythe numeral 1, having side Walls 8 and a bottom wall 9, andconcentrically disposed in the chamber 1 is an annular wall Ill forminga well H which has its bottom wall in the form of an annular U-shapedgroove l2. Extending outwardly from the upper extremities of the wall 8of the chamber is a plate It which is preferably provided with aplurality of apertures 14 and spaced below this plate is a plate I5,which may be integral with the upper surface of the block 6. The platel3 projects beyond the outer edge of the plate and may be connected toit by supporting pins l6. Extending downwardly from the centre of theplate I3 is a feed pipe I! having at its upper end a suitable fitting l8for connection to a pump, not shown, and at its lower end asubstantially frusto conical shroud I9, which shroud serves to directthe pulp towards the upperperipheral rim of the chamber 1. A pluralityof orifices 2B are formed along the upper edge of the wall 8 V of thechamber 1 and a plurality of openings 2! are formed along the lower edgeof said wall.

The total area of the feed pipe I? and that of the orifices appear tohave a definite relation and while good results are obtained with areasof widely varying proportions, best recovery has been hitherto obtainedwhere the areas are such that with a velocity of three discharging intothe well from the bottom of the feed pipe ll the velocity of flowthrough the orifices 20 equals four.

Mounted above the plate I3 is a dispersing plate 22, The underside ofthe dispersing plate slopes radially upwards towards its periphery as at23, so that the lighter particles of material rising into contact withit will move radially outward and impress their metallic content uponits amalgum coated surface.

Surrounding the rim 2 of the bowl I we pro vide an annular channel 24which is adapted to receive any small globules of mercury that pass outfrom the bowl and substantially fitting said channel is a flat copperring 25 which floats on the accumulated mercury. The upper level of thechannel 24 is some distance below the rim. Surrounding the channel 24 isan annular flange of copper 26 which is relatively fiat and has itsouter edge directly over the launder 3,

All the parts below the mercury level X and in contact with the mercurylevel are of copper or are coated with copper or other metal having anafiinity for mercury and the pulp contacting surfaces of the bowl I, thedispersing plate 22 and the channel 24 as at Z are of iron or othermaterial to which mercury will not adhere, so as to prevent the mercuryfrom creeping beyond its useful zone to facilitate the precipitation ofany mercury globules which may be in suspension in the water flowingupwards above the normal mercury level X.

In-operating the device, the bowl is filled with mercury to the line Xand liquid pulp is pumped through the feed pipe I! into the well llagainst the static pressure of the mercury therein, the ore content andwater will be forced upwards in a state of fine division due to themercury pressure and the larger particles of gold will be immediatelyencased in mercury, so that their amalgamation with the mercury maycommence, platinum and other metallic minerals of great specific gravitywhich cannot be amalgamated 55 will lag and precipitate into themercury. The lighter particles of gold, black sand and other unwantedmaterial will be carried upwards at an increasing rate of speed past thefrusto conical portion l9 and be projected through the orifices 20 andbetween the plates l and I3 into the space or zone Y where the velocityattained in passing through the orifies 20 will be rapidly reduced. Theoutward flow of pulp and mercury through the zone Y from each of theorifices will cause back eddies, causing ore laden water globules to bescrubbed with mercury and as some ore laden globules escape upwardsthrough the apertures l4 globules of mercury will descend through saidapertures to enter the radial stream. Such particles of gold which arenot immediately entrapped in the body of the mercury are worked by theflow through the zone Y onto the silvered surfaces of the plates l5 andiii, any values passing upwards through the orifices I4 will impingeupon the sloping surface 23 of the dispersing plate 22 and unwantedmaterial will creep along saidsurface to the periphery of the plate andwill then rise above the mercury level X and be carried over the rim 2across the channel 24 and the flange 26 to discharge into the launder 3.Any globules of mercury carried over the rim will impinge on the flatring 25, which being solid, will cause them to break up and eitheradhere to said ring or creep down into the channel 24, the tailingsflowing from the channel onto the flange 26 will due to the decreasingwater flow and reduction of stream depth, cause any remaining mercury tobe entrapped. 7

Mercury flowing beyond the peripheral edge of the plate I5 willcirculate in the bowl .and return to the chamber where it will againrise and inter-mix with the incoming pulp from the feed pipe ll. wallIll of the well II and the wall 8 of the chamber 1 is accelerated by thedifference in specific gravity of the liquid above it due to thepresence of water and that of the water free column of mercury betweenthe periphery of the block 6 and the bowl I.

What we claim as our invention is:

1. An amalgamator comprising a mercury bowl, a pulp feed pipe adapted todischarge below the mercury level in the bowl, a chamber within the bowlhaving vertical side walls and top and bottom walls, a cup mounted onthe bottom wall, said cup surrounding the discharge end of the feedpipe, a pair of spaced horizontal plates The rise of the mercury betweenthe adjacent the top and surrounding the chamber, said chamber wallshaving an orifice adjacent to the plates and communicating therebetweenand an orifice adjacent the bottom wall and in communication with thebase of the mercury bowl.

2. An amalgamator comprising a mercury bowl, a pulp feed pipe adapted todischarge below the mercury level in the bowl, a chamber within the bowlhaving vertical side walls and top and bottom walls, a cup mounted onthe bottom wall, said cup surrounding the discharge end ofthe feed pipe,a pair of spaced horizontal plates adjacent the top and surrounding thechamber, said chamber walls having an orifice adjacent to the plates andcommunicating therebetween and an orifice adjacent the bottom wall andin communication with the base of the mercury bowl, said platesconsisting of upper and lower plates and said upper plate extendingbeyond the lower plate.

3. An amalgamator comprising a mercury bowl,a pulp feed pipe adapted todischarge below the mercury level in the bowl, a chamber within the bowlhaving vertical side walls and top and bottom walls, a cup mounted onthe bottom wall, said cup surrounding the discharge end of the feedpipe, a pair of spaced horizontal plates adjacent the top andsurrounding the chamber, said chamber walls having an orifice adjacentto the plates and communicating therebetween and an orifice adjacent thebottom wall and in communication with the base of the mercury bowl, saidhorizontal plates serving to define a lateral fiow zone for the pulp andentrained mercury.

4. An amalgamator comprising a mercury bowl, a pulp feed pipe adapted todischarge below the mercury level in the bowl, a chamber within the bowlhaving vertical side walls and top and bottom walls, a cup mounted onthe bottom wall, said cup surrounding the discharge end of the feedpipe, a pair of spaced horizontal plates adjacent the top andsurrounding the chamber, said chamber walls having an orifice adjacentto the plates and communicating therebetween and an orifice adjacent thebottom wall and in communication with the base of the mercury bowl, anda dispersing plate disposed above the horizontal plates, said dispersingplate having a sloping undersurface, .said undersurface being inclinedin the direction of flow of pulp within the bowl.

WILLIAM ARTHUR GRANT. 'EDWARD FREEMAN ROACH.

